What is Dynamothermal metamorphism?
Dynamothermal metamorphism is due to the co-operation of directed pressure and heat. The heat element facilitates recrystallisation; but the stress element not only promotes recrystallisation, but is powerful in deforming the rocks, and producing new structures.
What is Dynamothermal or regional metamorphism?
A common type of metamorphism involving the effects of directed pressures and shearing stress as well as a wide range of confining pressures and temperatures. It is related both geographically and genetically to large orogenic belts, and hence is regional in character.
Where does Dynamothermal metamorphism occur?
Where does dynamothermal (regional) metamorphism take place? when rocks undergo heating and shearing during mountain building.
What causes Dynamothermal metamorphism?
Most metamorphic rocks are the result of regional metamorphism (also called dynamothermal metamorphism). These rocks were typically exposed to tectonic forces and associated high pressures and temperatures. They are usually foliated and deformed and thought to be remnants of ancient mountain ranges. Metamorphic grades.
What type of metamorphism would create a diamond?
Ultrahigh pressure metamorphism. In recent years high pressure minerals such as coesite and diamond have been found in metamorphic rocks. This type of metamorphism has been given the special name of ultrahigh pressure metamorphism (see below).
What is schist and gneiss?
Schist is a still higher degree of metamorphism, characterized by coarse grained foliation and/or lineation, with mica crystals large enough to be easily identified with the unaided eye. Gneiss is a medium to coarse-grained, irregularly banded rock with only poorly developed cleavage.
What does gneiss look like?
Gneiss is a tough, hard, coarse-grained metamorphic rock. It looks like it has ribbons or stripes of different coloured minerals running through it. It is usually light in colour, but it can be quite dark. It can look similar to granite.
What does schist look like?
Schist has a flat, large and sheet-like grains and It have flat and elongated minerals such as talc or micas.It has quartz and feldspar minerals are intertwined. These lamellar (flat, planar) minerals include micas, chlorite, talc, hornblende, graphite, and others.